CRACKS have appeared in what had seemed Arsenal's impregnability - now United have to ensure that they take full advantage.

The Reds will still be badly weakened by injury when Aston Villa visit Old Trafford tomorrow (Saturday), with Roy Keane, Ruud van Nistelrooy, Rio Ferdinand and Nicky Butt all unlikely to play.

But early qualification for the next phase of the Champions League has eased the pressure on Sir Alex Ferguson's squad.

And, with the Gunners and Liverpool threatening to turn the Premiership into a two-horse race, the Reds have to get their act together in the Premiership, regardless of staff shortages.

Goal-shy

The Gunners finally stumbled at Everton last week, but only the Scousers could take advantage as United needed Fabien Barthez to be on top form to grab a point at Fulham.

Such unconvincing, goal-shy displays have been a feature of the Reds' domestic form, while they have been dominant and free-scoring in the Champions League, with 14 goals in four games.

One boost tomorrow should be the return of ankle injury victim Ole Gunnar Solskjaer, who Fergie was unwilling to risk on a firm pitch in Piraeus.

Beckham worry

David Beckham, who left Greece wearing an ice pack on his left ankle, is also expected to play against Graham Taylor's struggling team, who have yet to score in losing all four of their four Premiership away games so far this season.

Qualification in the Champions' League means that Fergie can use the two remaining games as fresheners for his fringe players, and concentrate on clawing back the six-point gap between themselves and leaders Liverpool.

Taylor brings his Villa side to Old Trafford with plenty of pressure on his own shoulders - Monday night's defeat at Southampton was the sixth in 10 games, and there were cries of "Taylor out!" from Villa fans who once worshipped him.

Taylor will be hoping that ex-United defender Ronny Johnsen will recover from a thigh strain which kept him out of the Saints game.

And German under-21 midfielder Thomas Hitzlsperger, who impressed in his Premiership debut against United last February, is available again after being ruled out of action since August with a stomach muscle injury.

Last season: Man Utd 1 Aston Villa 0

Key Opponent: Ronny Johnsen - if fit, the former United player will be keen to impress.